Automotive muffler having means for switching between loud and quieter modes

ABSTRACT

An automotive muffler having a device for switching between loud and quieter modes includes a chamber having an inlet exhaust pipe and an outlet exhaust pipe for the passage of exhaust gases through the chamber. The first section of the chamber has a plurality of baffles with openings through the baffles for the passage of the exhaust gases. A second section of the chamber, separated from the first section of the chamber, permits a substantially unobstructed passage of exhaust gases through the second section of the chamber to the outlet exhaust pipe. A switching device is able to be selectively switched between diverting incoming exhaust gases substantially through only the first section of the chamber and diverting incoming exhaust gases substantially though only the second section of the chamber, so that when the exhaust gases are substantially diverted through only the first section of the chamber having the baffles, the automotive muffler is operated in a quiet mode and when the exhaust gases are substantially diverted through only the second section of the chamber, the automotive muffler is operated in a loud mode.

BACKGROUND OF THE INVENTION

1. Technical Field of the Invention

The present invention relates, generally, to an improved muffler forautomotive use which includes means for switching between loud andquieter modes.

More particularly, the present invention relates to an improved mufflerfor high performance that would be useful for all types of automobiles,but which would preferably be used in the commercial trucking industry,which would allow the driver of the vehicle to readily switch from aquiet mode with backpressure to a loud, or louder, mode with nobackpressure. The means for switching from the quiet mode to the loudmode would be able to be actuated from within the car or truck cab.

2. Description of the Prior Art

Currently known to the prior art, and commercially available, aremufflers that employ so-called “dumper valves,” which are generally usedin the high-performance automobile industry. These dumper valve mufflerspermit drivers to switch from a quiet mode to a loud mode from withinthe vehicle, however, when these types of mufflers are in the loud mode,all gases are dumped underneath the vehicle, as opposed to exiting fromthe vehicle's exhaust system.

Because dumper valve mufflers dump vehicle gases underneath the vehicle,such mufflers are not generally permitted to be used in the truckingindustry, unless the truck is specially fitted with additional exhausttubing at considerable expense, which adds to the weight of the truckand would necessarily increase operating expense as fuel mileage isdecreases.

Heretofore, the prior art fails to provide or suggest the use of aloud/quiet muffler that is readily able to be switched between quiet andloud modes from within the vehicle, which does not require additionalexhaust tubing, which would otherwise be required for many types ofvehicles, particularly those in the trucking industry.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to provide anautomotive muffler having means for switching between loud and quietmodes, which avoids the requirement of providing additional exhausttubing otherwise required for such types of mufflers.

It is a further object of the present invention to provide an automotivemuffler having means for switching between loud and quiet modes, whichmaintains the appearance of a conventional muffler.

It is, yet, an additional object of the present invention to overcomethe disadvantages inherent in prior art mufflers that are capable ofswitching between loud and quiet modes.

The foregoing and related objects are achieved by the automotive mufflerof the present invention, which includes means for switching between aquiet mode to a loud mode, and vice versa, from within the car or truckcab. The muffler of the invention includes chamber through which exhaustgases are passed through. The chamber is divided into two sections inthe direction of flow of the exhaust gases. The first section of thechamber includes a series of baffles, which have a series of openingstherethrough, are preferably angled for permitting the ready passage ofexhaust gases through the first section of the chamber. As exhaust gasesare passed through the first section of the chamber having the pluralityof baffles, the muffler is quieted and may be considered to be in the“quiet” mode.

The second section of the chamber of the muffler does not have anybaffles and exhaust gases are able to pass through this second sectionof the chamber, and exit the chamber, without obstruction. When exhaustgases pass through this second section of the chamber, the muffler maybe considered to be operating in its “loud” mode.

The chamber is provided with a selection flap, which directs exhaustgases exclusively to either the first section of the chamber, when themuffler is to be operated in the quiet mode, or to the second section ofthe chamber, when the muffler is to be operated in the loud mode. Theselection flap, which may be controlled and activated from within thevehicle, may be thought of as being operable in a fashion similar to theselection flaps of the vehicle's heating and air-conditioning system,which may either permit, or not permit, outside air to enter thevehicle's passenger compartment. It is submitted that the preciseconstruction of the selection flap, or other selection means, fordiverting exhaust gases through exclusively either the first section orthe second section of the chamber of the inventive muffler, is wellwithin the skill of one having ordinary knowledge of the relevant art.

Other objects and features of the present invention will become apparentwhen considered in combination with the accompanying drawing figureswhich illustrate certain preferred embodiments of the present invention.It should, however, be noted that the accompanying drawing figures areintended to illustrate only certain embodiments of the claimed inventionand are not intended as a means for defining the limits and scope of theinvention.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

In the drawing, wherein similar reference numerals and symbols denotesimilar features throughout the several views:

FIG. 1 is a perspective view of the automotive muffler having means forswitching between loud and quieter modes, in which the chamber thereofis divided into two sections in the direction of the flow of exhaustgases with the first section of the chamber having a plurality ofbaffles and the second section of the chamber allowing for theunobstructed passage of exhaust gases;

FIG. 2 is an elevational view of the automotive muffler having means forswitching between loud and quieter modes, in which exhaust gases areshown passing through plurality of baffles of the first section of thechamber of the muffler when the muffler is switched to “quiet” mode;and,

FIG. 3 is an elevational view of the automotive muffler having means forswitching between loud and quieter modes, in which exhaust gases areshown passing in an unobstructed manner through the second section ofthe chamber of the muffler when the muffler is switched to “loud” mode.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS AND DRAWING FIGURES

Turning now, in detail, to an analysis of the drawing figures, FIG. 1 isa perspective view of the automotive muffler 10 having means forswitching in the form of a switch flap 12, for switching muffler 10between quiet mode and loud mode within chamber 14. Chamber 14 isdivided into two sections, 14 a, 14 b. Internal wall 20 provides adivision of chamber 14 into first section 14 a and second section 14 bin the direction of flow of the exhaust gases. Vehicle exhaust gasesenter chamber 14 in the direction of the arrow leading to exhaust inletpipe 16 a and, after passing through chamber 14, ultimately exit throughexhaust outlet pipe l 6 b, in the direction of the outlet arrow. In FIG.1, switch flap 12 is arbitrarily shown as blocking the circular openingto second section 14 b of chamber 14, which would divert incomingexhaust gases into, and through, first section 14 b of chamber 14.

The first section 14 a of chamber 14 includes a plurality of baffles 18a, 18 b, 18 c, 18 d, 18 e, 18 f. The precise number of baffles is amatter of design choice and would depend, in large measure, upon thedimensions of the muffler actually manufactured. The baffles 18 arepreferably angled in a direction that would tend to allow the exhaustgases to pass through the first section 14 a of chamber 14 in thedirection of flow from inlet exhaust pipe 16 a to outlet exhaust pipe 16b. The preferred construction of baffles 18 is illustrated in FIG. 1,though other shapes and sizes of the plurality of baffles are possibleand within the scope of the present invention.

When switch flap, or selection flap, 12 blocks second section 14 b, asillustrated in FIG. 1, the muffler will be in its “quiet” mode. Switchflap, or selection flap, 12 can be flipped to block the opening leadingto first section 14 a, in which situation incoming exhaust gases arediverted through second section 14 b of chamber 14 and out throughoutlet exhaust pipe 16 b, resulting in the inventive muffler being inits “loud” mode.

FIG. 1 further illustrates baffles 18 as each having circular openingsfor exhaust gases to pass therethrough. Obviously, the number and shapeof the openings of the baffles is a matter of design choice and all suchdesign choices, shapes and sizes, are within the skilled of the ordinaryartisan and within the scope of the present invention.

FIG. 2 is an elevational view of the automotive muffler 10 having meansfor switching, via switching flap 12, between loud and quiet modes, inwhich exhaust gases are shown passing through (in the direction of themultiplicity of arrows shown in FIG. 2) a plurality of baffles 18 of thefirst section 14 a of the chamber 14 of the muffler 10 when the muffleris switched to “quiet” mode. Switch flap 12 is shown blocking theopening to second section 14 b of chamber 14, thereby necessarilydiverting exhaust gases into the first section 14 a of the chamber.

FIG. 3 is an elevational view of the automotive muffler 10 having meansfor switching, via switching flap 12, between loud and quiet modes, inwhich exhaust gases are shown passing through (in the direction of themultiplicity of arrows shown in FIG. 3) the “baffle-free” second section14 b of the chamber 14 of the muffler 10 when the muffler is switched to“loud” mode. Switch flap 12 is shown blocking the opening to firstsection 14 a of chamber 14, thereby necessarily diverting exhaust gasesinto the second section 14 b of the chamber.

It will be apparent to the skilled artisan that modification to theshape of the chamber and the relative sizes of each of the sections ofthe chamber, as well as the plurality of baffles and the openingstherein, can be readily made and are all within the scope of the presentinvention.

Likewise, means for switching between diversion of exhaust gases intothe first section of the chamber, as opposed to the second section ofthe chamber, or vice versa, can be accomplished in numerous ways. It isnot essential that a switch flap be used. Any means for switching thediversion of exhaust gases into one section of the chamber of themuffler, to the exclusion of the other chamber of the muffler, willsuffice.

While only several embodiments of the present invention have been shownand described, it will be obvious to those skilled in the art that manymodifications may be made to the present invention without departingfrom the spirit and scope thereof.

1. An automotive muffler having means for switching between loud andquieter modes, comprising: a chamber having an inlet exhaust pipe and anoutlet exhaust pipe for the passage of exhaust gases through saidchamber; a first section of said chamber having a plurality of baffleswith openings through said plurality of baffles for the passage of theexhaust gases; a second section of said chamber separated from saidfirst section of said chamber for permitting the substantiallyunobstructed passage of exhaust gases therethrough to the outlet exhaustpipe; and, means for selectively switching between diverting incomingexhaust gases substantially through only said first section of saidchamber and diverting incoming exhaust gases substantially though onlysaid second section of said chamber, so that when the exhaust gases aresubstantially diverted through only said first section of said chamberhaving said plurality of baffles, said automotive muffler is operable ina quiet mode, and when the exhaust gases are substantially divertedthrough only said second section of said chamber, said automotivemuffler is operable in a loud mode.
 2. The automotive muffler havingmeans for switching between loud and quieter modes according to claim 1,wherein said plurality of baffles of said first section of said chamberare angled for allowing the ready passage of the exhaust gasestherethrough.
 3. The automotive muffler having means for switchingbetween loud and quieter modes according to claim 1, wherein saidplurality of baffles of said first section has circular openings passingtherethrough.
 4. The automotive muffler having means for switchingbetween loud and quieter modes according to claim 1, wherein said meansfor selectively switching means for switching between diverting incomingexhaust gases substantially through only said first section of saidchamber and diverting incoming exhaust gases substantially though onlysaid second section of said chamber includes a switching flap forsubstantially blocking an opening to either said first section or saidsecond section of said chamber, thereby diverting the exhaust gases toeither said second section or said first section, respectively, that isunblocked by said switching flap.
 5. The automotive muffler having meansfor switching between loud and quieter modes according to claim 4,wherein said switching flap is operable by a driver of a vehicle havingsaid automotive muffler from a passenger compartment of the vehicle.